Ah yes, I've read about this before. You want to leave your bed unmade for at least a few hours, unmade and exposed. But sunlight is also great. Sunlight exposure kills mites. You can sun lots of things to make them safer. The thing to remember though is that you don't actually react to the mites. You react to the things the mites excrete and to dead mite bodies. So, if you have a lot of dust mites and kill them, things may get worse for a bit. So, killing them and washing the sheets and then regularly airing and sunning them is probably best.

Also, carpets are massive allergen risks. When I can afford it, I want to get myself one of those really nice HEPA filter bagless vacuums. I've used a friend's, and it's great. Powerful, easy to use, easy to clean out. And vacuuming the carpet in your bedroom regularly with a good vacuum is one of the biggest things you can do to decrease allergy issues.